1. Field of Invention
The present invention relates to a game system for executing video games on a computer and a computer program thereof.
2. Disclosure of the Prior Art
In a video-game field, it has been already known that there are games advanced stepwise in units of stages from a one of a lower difficulty level to that of a higher difficulty level. For example, in a shooting-game, a combat plane or the like to be operated by a user is arranged on one side of a map, which is a field, in a first stage. The user makes his/her plane move on the map. At this moment, the player must make his/her plane evade obstructions, e.g. constructions, arranged on the map, missiles shot from the enemy planes appearing on the map, and so on. On the other hand, the user obtains items to make the function of his/her plane improve so that the own plane speeds up, the own missile power increases and so on. These items are arranged on the map or appear by shooting down the enemy planes. The obstructions are constructed, subject to the function of the user's plane improving by getting the items to make the function improved, so that the number of the obstructions increases or the move of which becomes quicker and more complicated as advancing the map. Namely, the game is constituted so that the difficulty level thereof gets higher corresponding to the game's progress. If the game becomes over when his/her plane hits some obstructions halfway, the player must start the game from the first stage again. If a predetermined condition, e.g., his/her plane arrives at the opposite side of the start position, is satisfied, he/she is allowed to advance the game to the next stage.
To satisfy users, game-makers prepare data and programs so that various items to improve the function and obstructions appear on the map to thereby provide elaborate games.
In such games, there is a great difference between the skill of the beginners and the skill of the experienced players. Consequently, if the game is constructed to meet the level of the experienced players, there is a possibility for the beginners to lose their interest immediately because they can progress only to a certain stage. Furthermore, there is a problem they stop playing the game though some contents, not yet played, remain.
On the other hand, if the game is constructed to meet the level of the beginners, the experienced players are not satisfied enough because they can complete the game in a short time. Because of that, for the even experienced players to play for a long time and be satisfied with the game, there is a need for extra-stages for only the experienced players. Therefore, the software developers must design programs and data to realize such stages; thus, there is a problem that the workload of the developers increases.